Wolfram Mathematica

anderstood

01:50

NDSolve has a bug (memory leak) up to at least 11.0.0. Can someone with 11.0.1 tell me if this issue is solved in 11.0.1? Depending on the answer, I will upgrade or not. The code to try the one in the last block of mathematica.stackexchange.com/a/123639/18767. Thank you

DAE = ({{x1'[t] == x3[t]}, {x2[t] (1 - x2[t]) ==
0}, {x1[t] x2[t] + x3[t] (1 - x2[t]) == t}});
Clear[old, x, y]
ClearSystemCache[];
MemoryInUse[]
Do[old = MemoryInUse[];
NDSolve[{DAE, x1'[0] == 1}, {x1, x2, x3}, {t, 0, 1}];
Print[MemoryInUse[] - old];, {10}]
MemoryInUse[]

The memory in use should not increase after multiple runs.

yode

05:54

@Xavier Wow,I'm sorry I I have been misunderstood you,but I remeber I have seem your nickname in Chinese forum.

Yes,the google translaton is my meaning.I'm very desire to get a bug fixed list about that function intrduced 10 especially.Thanks for your current endeavor. :)

Vitaliy Kaurov

09:19

Beyond Four Corners, USA
http://community.wolfram.com/groups/-/m/t/932548

Michael E2

14:28

@yode @Xavier There is the bug-tracker, which depends on posts have the standard bugs header

yode

15:05

@MichaelE2 Wow,This is what I want exactly,but it seem to won't update anymore?

user147238

@yode here is the source

yode

@Xavier Hello,happy to see you online.As I think about the action of this post,I think this bug is still.How do you think?

Reap[RelationGraph[True & @@ Sow[{##}] &, Range[3], Range[4, 7]]]

It will give two {1,4} in 11.0.1.Of course,it will give a worse result in 11.0 or before version.

user147238

15:21

@yode Hi. I'd say these are two different bugs, but probably closely related. Let me have another look.

yode

Different?

user147238

well, one is fixed in 11.0.1 and the other not, so I suppose the bug is not the same. If it is, the correction of the bug was not made general enough? I cannot say, I've to give a closer look at your post first.

user147238

you can run the code in the source I linked to have the updated version (didn't try myself)

user147238

15:37

@yode both seem to be fixed in 11.0.1 actually. I may have checked the latter in 11.0.0 but forgot to check it in 11.0.1

user147238

ah wait no...

user147238

I was being confused with the code you wrote and the one you have in the image

user147238

@yode so this bug is about the two-argument form of RelationGraph, and the issue with duplicates

user147238

a simpler code would be: RelationGraph[#1 < 4 && #2 >= 4 &, {1, 1, 2, 3, 4, 5, 6, 7, 8, 9}]

user147238

this fails from 10.2 to 11.0.1

user147238

15:47

if you remove the duplicates, this works in all versions

user147238

I don't get the vertex labels with RelationGraph[#1 < 4 && #2 >= 4 &, {1, 1, 2, 3, 4, 5, 6, 7, 8, 9}] however in 11.0.1, but I have them without the duplicates.

user147238

@yode this other bug is about the three-argument form of RelationGraph

user147238

I get error messages in both 11.0.0 and 11.0.1, although not the same.

user147238

"this fails from 10.2 to 11.0.1" ---> "this fails from 10.2 to 11.0.0"

J. M.

@Xavier, if you made a mistake in anything you typed in the chatroom, you have a small window of time to edit it; just press the up arrow key.

user147238

15:55

@J.M. OK, thanks.

user147238

@yode I think those are two different wrong behaviors

user147238

16:16

About the graph and code you posted in the chat, RelationGraph was doing unnecessary evaluations, which has been fixed in 11.0.1. About the presence of two {1,4}, it seems that RelationGraph evaluates once the test function on the first element of the first list (Range[3]) and of the second list (Range[4, 7]). If it does not evaluate to True or False, the algo of RelationGraph will stop; otherwise it will continue.

user147238

Compare for instance Reap[RelationGraph[(Sow[{##}]; Mod[#1, #2] == 2) &, {1, 2, 3}, Range[4, 7]];]

user147238

to Reap[RelationGraph[(Sow[{##}]; Mod[#1, #2] == 2) &, {"a", 2, 3}, Range[4, 7]];].

user147238

This is probably some safety feature. RelationGraph considers that if its check did not yield True or False, the lists or the test function are not properly constructed, so it doesn't bother evaluating the test function on all elements.

user147238

Plot is doing some extra evaluations as well (not for the same reason). Evaluate for instance Reap[Plot[Sow[x], {x, -1, 1}, MaxRecursion -> 1, PlotPoints -> 2];]

sky-light

17:00

Hi

In Mathematica 9.0, how do I set the precision back to the default value?
I used this line to increase the precision

$PreRead = (# /.
s_String /;
StringMatchQ[s, NumberString] &&
Precision@ToExpression@s == MachinePrecision :>
s <> "`30." &);

However, it ruined my calculations. Now I want to move back to the default settings.

yode

17:33

@Xavier Thanks for your so kind analysis.But considering this code（Reap[RelationGraph[(Sow[{##}]; Mod[#1, #2] == 2) &, {1, "a", 3},
Range[4, 7]]]）can run normally,I think this is a strange behavior still.

It can give a edge just when the case is True.

user147238

17:56

@yode Yes, the check test is only performed on the first element of the two lists. At this point, I think this is only a choice of design by the developers. The first check test must return True or False for the algorithm to proceed. If this is not wanted, one could wrap the test function in a TrueQ to get the full evaluation in the first situation: Reap[RelationGraph[(Sow[{##}]; TrueQ[Mod[#1, #2] == 2]) &, {"a", 2, 3}, Range[4, 7]];].

user147238

@sky-light What about doing $PreRead=.?

user147238

@yode I am thinking that this safety feature makes sense when giving a bad test function, such as an undefined symbol f, rather than "bad" vertices.

yode

So you think this is reasonable?

user147238

I would say so. It prevents evaluations when a test function is badly constructed (or simply not a test function), e.g. ClearAll[f]; Reap[RelationGraph[(Sow[{##}]; f[#1, #2]) &, Range[10^6], Range[10^6]];].

yode

@Xavier Thanks again. :)

user147238

18:15

Also, for this last code, if the condition of having True or False on the first check was not done, and since an evaluation to something else than True and False is effectively considered as False for all the other checks, you would just end up with a graph of not-connected vertices, for any badly constructed test function.

user147238

This may not be useful when asking for a relation graph.

user147238

18:32

@yode There are implementations where no check is done, and the evaluation is performed completely. For instance, ContainsAll[{"A", "B", "C"}, {"a", "b"}, SameTest -> (Echo@f[##] &)]. So in the end, I think this is just a choice of design done by each developer.

yode

Your new example is very Interesting.I think I know your meaning totally now. :)@Xavier

In the end I ask again,do you think this behavoir is bug now?

@Xavier I think our discuss is concern this.

"the three-argument"

It will do some combination,too.

So I think they are same problem.

user147238

20:21

@yode I think the behavior you linked is a bug, unrelated to the other. In the first bug you wrote, whose simplified version is RelationGraph[#1 < 4 && #2 >= 4 &, {1, 1, 2, 3, 4, 5, 6, 7, 8, 9}], the combination are down within the same list. This is expected in view of the first usage line of the ref page: "... whenever f[vi, vj] is True."

user147238

Somehow, having a duplicate vertex messed up the computation, and this was fixed in 11.0.1. Compare for instance in 10.4.1 and 11.0.1: Reap[RelationGraph[(Sow[{##}]; #1 < 4 && #2 >= 4) &, {1, 1, 2, 3, 4, 5, 6, 7, 8, 9}]][[2, 1]].

user147238

@yode In the behavior you linked, there was combinations of elements in the same list, which should not have happened in view of the second usage line: "... whenever f[vi, wj] is True."

user147238

You can compare now Reap[RelationGraph[(Sow[{##}]; #1 < 4 && #2 >= 4) &, {1, 2, 3}, {4, 5, 6}]][[2, 1]] in 10.4.1 and 11.0.1. The wrong combinations happen in 10.4.1 but not anymore in 11.0.1.

user147238

You can see that what you underlined in red in your post does not happen anymore in 11.0.1. Combinations from elements of the same list is not done anymore.

user147238

There are however still unnecessary/uncorrect evaluations in 11.0.1, as reported by the error messages. Those were in 10.4.1 and are still in 11.0.1. RegionMember[#1, #2] & evaluates in RelationGraph as RegionMember[#1, #2] & and as RegionMember[#2, #1] &, which should not happen.

user147238

20:40

I think those are the not the same problem, but maybe we are not using the same terminology, hence the disagreement.

user147238

@yode Ah sorry, I think I understand now. "RegionMember[#1, #2] & evaluates in RelationGraph as RegionMember[#1, #2] & and as RegionMember[#2, #1] &, which should not happen." ---> This is not correct. The test function needs not to be symmetric, in which case one will end up with directed graphs.

user147238

So yeah, this bug seems to be fixed as well.

user147238

I am not sure though that this is the same problem as the other bug, but I may be mistaken again. I'll have yet another look.

user147238

22:24

@yode I think I have a clearer picture about what was happening for this post. I have made an answer with my current understanding.

Manuel Odendahl

22:47

i am trying to make a notebook where you can load a csv file by clicking a button, and then all the manipulates populate and all. So this is kind of working, but upon initial loading, all the manipulates have no data and throw funny errors. What's a proper way to get around this.

anderstood

Can someone with MMA 11.0.1 can try this code and see if the memory in use increases (memory leak) ?

DAE = ({{x1'[t] == x3[t]}, {x2[t] (1 - x2[t]) ==
0}, {x1[t] x2[t] + x3[t] (1 - x2[t]) == t}});
Clear[old, x, y]
ClearSystemCache[];
MemoryInUse[]
Do[old = MemoryInUse[];
NDSolve[{DAE, x1'[0] == 1}, {x1, x2, x3}, {t, 0, 1}];
Print[MemoryInUse[] - old];, {10}]
MemoryInUse[]

@ManuelOdendahl It's hard to help without any code.

Manuel Odendahl

kk, will to get something up

should i upload the notebook somewhere?

bl0rg.net/~manuel/timeseries.zip

i'm trying to tackle Dynamic and all that and my brain is melting a bit

anderstood

@ManuelOdendahln Why don't you i) check the documentation, ii) check that your question has not been asked before, iii) post a new question if i) and ii) did not help you?

Manuel Odendahl

i am not sure my question is not open ended and thus not relevant for SE

i read the doc quite a bit but there's not much in the "make a self contained app loading data from files" way, there's some examples of using SystemDialogInput but they are all fairly trivial

Manuel Odendahl

23:48

i've something halfway workable. I'm sure i'll get to meet people who know this stuff at the tech conf

Transcript for